Fragmented sleep - fragmented mind : the role of sleep in dissociative symptoms Citation for published version (APA): van der Kloet, D. (2013). Fragmented sleep - fragmented mind : the role of sleep in dissociative symptoms. Universitaire Pers Maastricht. https://doi.org/10.26481/dis.20131115dk Document status and date: Published: 01/01/2013 DOI: 10.26481/dis.20131115dk Document Version: Publisher's PDF, also known as Version of record Please check the document version of this publication: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. 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If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license above, please follow below link for the End User Agreement: www.umlib.nl/taverne-license Take down policy If you believe that this document breaches copyright please contact us at: [email protected] providing details and we will investigate your claim. Download date: 29 Sep. 2021 Fragmented Sleep – Fragmented Mind The Role of Sleep in Dissociative Symptoms ISBN 978 94 6159 258 3 © copyright Dalena van Heugten – van der Kloet, Maastricht 2013 Cover design by Rob van Heugten & Michael Warlich Cover models: Eva, Stephanie, & Kirsten Printing: Datawyse / Universitaire Pers Maastricht Fragmented Sleep – Fragmented Mind The Role of Sleep in Dissociative Symptoms DISSERTATION to obtain the degree of Doctor at Maastricht University, on the authority of the Rector Magnificus, Prof. dr. L.L.G. Soete, in accordance with the decision of the Board of Deans, to be defended in public on Friday 15 November 2013, at 12.00 p.m. by Dalena van Heugten – van der Kloet U MP UNIVERSITAIRE PERS MAASTRICHT Supervisor Prof. dr. H.L.G.J. Merckelbach Co‐supervisors Dr. T. Giesbrecht, Unilever R&D, Vlaardingen Assessment Committee Prof. dr. A. Arntz (chairman) Prof. dr. D. P. Bernstein Prof. dr. B. M. Elzinga, Universiteit van Leiden Prof. dr. J. van Os Dr. J.P. Wessel, Universiteit van Groningen CONTENTS Chapter I General introduction 7 PART I: CAUSAL FRAMEWORK 35 Chapter II Sleepiness predicts the increase of dissociative symptoms: A field study 37 Chapter III Dissociative symptoms and sleep parameters ‐ An all‐night polysomnogra‐ 47 phy study in patients with insomnia Chapter IV Night‐time experiences and daytime dissociation: A structural equation 61 modeling study. PART II: UNDERLYING MECHANISMS 75 Chapter V Sleep loss increases dissociation and affects memory for emotional stimuli 77 Chapter VI Recreational doses of MDMA, THC, and cocaine produce dissociative symp‐ 99 toms Chapter VII Self‐reported sleep disturbances in patients with dissociative identity 111 disorder and how they relate to cognitive failures and fantasy proneness PART III: TREATMENT OF DISSOCIATIVE SYMPTOMS 121 Chapter VIII Decreasing dissociative symptoms using sleep hygiene recommendations: 123 An exploratory study Chapter IX Mindfulness Based Therapy improves sleep, but not dissociative symptoms 137 Chapter X Sleep normalization and decrease in dissociative experiences: Evaluation in 147 an inpatient sample GENERAL DISCUSSION 169 Summary 182 Samenvatting 184 References 186 Dankwoord 206 Curriculum Vitae 207 List of publications 208 CHAPTER I1 General introduction 1 This chapter is an adapted version of the following articles and book chapter: Van der Kloet, D. (Forthcoming). Dissociative disorders: The relation between dissociation, trauma, and sleep problems. In R. Biswas‐Diener & E. Diener (Eds), Noba textbook series: Psychology. Champaign, IL: DEF Publishers. DOI: www.nobaproject.com Van der Kloet, D., Merckelbach, H., Giesbrecht, T., & Lynn, S.J. (2012). Fragmented sleep, fragmented mind: The role of sleep in dissociative symptoms. Perspectives on Psychological Science, 7, 159‐175. Van der Kloet, D., & Merckelbach, H. (2010). Waar dissociatie vandaan komt – het schemergebied tussen slapen en waken. GZ‐Psychologie, 7, 12‐21. 7 8 General introduction Summary In psychopathology, dissociation typically refers to a disturbance in the normal integration of thoughts, feelings, and experiences into consciousness and memory. In this chapter, we review the literature on how sleep disturbances relate to dissociative symptoms and cognitive aberrations seen in dissociative disorders. We contend that this body of research offers a fresh perspective on the origins of dissociation. Specifically, we argue that dissociative symptoms are associated with a labile sleep‐wake cycle in which dreamlike mentation invades the waking state, sleep loss produces memory failures, and fuels dissociative experiences. The research domain of sleep and dissociation does not contradict the dominant idea in the clinical literature that trauma is the distal cause of dissociation, and holds substantial promise to inspire new treatments for dissociative symptoms (e.g., interventions that focus on normalization of the sleep‐wake cycle). We conclude with worthwhile paths for further investigations and suggest that the sleep‐ dissociation approach may help reconcile competing interpretations of dissociative symptoms. 9 Chapter I Introduction Dissociative disorders encompass an array of symptoms associated with alterations in consciousness, ranging from profound amnesia for autobiographical events, to equally profound problems in identity and changes in the experience of everyday reality (DSM‐IV‐TR; American Psychiatric Association (APA), 2000). The dominant perspective on dissociative symptoms is that they reflect a defensive response to highly aversive events, especially psychological trauma during the formative childhood years (Bremner, 2010; Spitzer, Vogel, Barnow, Freyberger, & Grabe, 2007; Spiegel, Loewenstein, Lewis‐Fernandez, Sar, et al., 2011). We will refer to this perspective as the posttraumatic model (PTM) of dissociation. An impressive corpus of research has succeeded in elucidating the relation between dissociative symptoms and a gamut of psychological disorders, cognitive processes, and behaviors (for a review, see Giesbrecht, Lynn, Lilienfeld, & Merckelbach, 2008). In this chapter, we suggest that sleep disturbances play a potentially important role in accounting for dissociative symptoms and how they relate to highly aversive events. We will argue that there now exists a solid foundation of research to contend that dissociative symptoms are associated with a labile sleep‐wake cycle in which dreamlike mentation invades the waking state, produces memory failures, and fuels dissociative experiences. Whereas this chapter builds on previous contributions (e.g., Giesbrecht et al., 2008; Koffel & Watson, 2009a,b; Watson, 2001) indicating that dissociation and sleep disturbances belong to a common domain, in the current chapter we provide the most comprehensive analysis of studies on sleep and dissociation to date in both tabular and narrative form. In so doing, we (a) consider important definitional issues and limitations of the prevailing PTM; (b) describe the main findings and clinical ramifications of studies that examine the sleep‐dissociation link; (c) discuss evidence pertaining to the causal relation between sleep and dissociation, and (d) suggest that the studies reviewed may provide a basis for not only understanding the association between highly aversive events and dissociation, but also a rapprochement between the PTM and interpretations that emphasize a non‐traumatic etiology of dissociation (Lilienfeld, Lynn, Kirsch, Chaves, Sarbin, Ganaway, & Powell, 1999; Spanos, 1996). We conclude with suggestions for extending the sleep‐dissociation model and call for future research on the link between sleep and dissociation. Defining Dissociation The DSM‐IV‐TR defines dissociation as “a disruption in the usually integrated function of consciousness, memory, identity, or perception of the environment” (APA, 2000, p. 519). In the clinical literature, a distinction is often made between dissociative states and dissociative traits (e.g., Bremner, 2010; Bremner & Brett, 10 General introduction 1997). Whereas state dissociation is viewed as a transient symptom (e.g., acute dissociation during a traumatic event), trait dissociation is viewed as an integral aspect of personality. As dissociative symptoms are prevalent in both nonclinical and clinical populations, dissociation has commonly been conceptualized as ranging on a continuum, from non‐pathological manifestations of daydreaming to